This is a request to establish a Center for Behavioral Sciences Research (CBSR) focused on social and psychobiological contributions to affective style at the University of Wisconsin-Madison. Affective style refers to the broad range of individual differences in emotion-related processes. We will approach the issue of affective style from a myriad of perspectives in four projects, supported by three cores. Project 1, will examine relations among patterns of regional brain electrical activity, regional glucose metabolism (assessed with positron emission tomography) and emotion-modulated startle in subjects selected on the basis of extreme left or right or symmetrical prefrontal or anterior temporal brain electrical activity measures. Another experiment will assess electrophysiological measures of regional brain activity and autonomic indices in the mothers and fathers of the twins to be tested in Project II. In Project II monozygotic and dizygotic twins will be assessed at 6 and 12 months of age on behavioral measurements of temperament. In addition, they will be assessed on electrophysiological measures of regional brain function, measures of heartrate and respiratory sinus arrthymia and activity in the hypothalamic-pituitary- adrenal (HPA) system via measures of salivary cortisol. In Project III the physiological correlates and biological substrates of behavioral inhibition will be examined in rhesus monkeys. Differences between extremely inhibited and less inhibited monkeys in activity in the HPA axis, autonomic activity and regional brain electrical activity will be examined. Differences in the acquisition and extinction of learned fearful responses will also be studied in the different groups. Autoradiography will be used to examine the density and distribution of benzodiazepine receptors and c-Fos techniques will be used to characterize the specific neural circuits that participate in responses to fearful stimuli. In Project IV data will be analyzed from an existing corpus available from the NIMH- funded Wisconsin Maternity Leave and Health Project. Videotaped interactions between mothers and infants at ages four and twelve months will be coded for quality of affective communication. The influence of maternal affective style on the affective quality of the exchange will be studied and the social mediators of this relationship (such as demographic characteristics, personal resources, social support) will be examined. A second study will investigate the impact of individual differences in infant temperament on the course of personality and depressive symptoms in the mothers. Social mediators of this relation will also be examined. These projects will be supported by Administrative, Behavioral Assessment and Biological Measures Cores. This Center will significantly advance our understanding of the social, psychological and biological bases of individual differences in affective style and yield important new information that will facilitate our understanding of disorders of emotion.